Answer
(a) 17
(b) 5
Work Step by Step
a) The slope of the secant line=
$\frac{f(2+h)-f(2)}{h}=\frac{3h^{2}+5h}{h}=3h+5$
$h=6-2=4$. Therefore,
the slope of the secant line=$3\times4+5=17$
b) $f'(2)=\lim\limits_{h \to 0}\frac{f(2+h)-f(2)}{h}=\lim\limits_{h \to 0}3h+5=5$